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Protection Features
Check out our PSUs 101 article to learn more about PSU protection features.
|
OCP (Cold @ 24°C) |
12V: 122.8A (147.42%), 11.937V |
|
OCP (Hot @ 43°C) | 12V: 122.4A (146.94%), 11.901V 5V: 32.3A (129.2%), 4.970V 3.3V: 33.2A (132.8%), 3.292V 5VSB: 5.4A (180%), 4.981V |
|
OPP (Cold @ 25°C) |
1479.06W (147.91%) |
|
OPP (Hot @ 43°C) |
1469.76W (146.98%) |
|
OTP |
✗ (>200°C @ secondary side) |
|
SCP |
12V to Earth: ✓ |
|
PWR_OK |
Proper operation |
|
NLO |
✓ |
|
SIP | Surge: MOV Inrush: NTC Thermistor & Bypass relay |
We don't see an SFX-L PSU delivering close to 1500W every day. This is a real power factory! That said, the +12V OCP and the OPP triggering points should be set more conservatively, at around 130%. Another downside is the lack of over-temperature protection, which can save the day if something goes wrong with the PSU's cooling.
DC Power Sequencing
According to Intel’s most recent Power Supply Design Guide (revision 1.4), the +12V and 5V outputs must be equal to or greater than the 3.3V rail at all times. Unfortunately, Intel doesn't mention why it is so important to always keep the 3.3V rail's voltage lower than the levels of the other two outputs.
The 3.3V rail is always lower than the other two, so everything is fine here.
Cross Load Tests
To generate the following charts, we set our loaders to auto mode through custom-made software before trying more than 25,000 possible load combinations with the +12V, 5V, and 3.3V rails. The deviations in each of the charts below are calculated by taking the nominal values of the rails (12V, 5V, and 3.3V) as point zero. The ambient temperature during testing was between 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit).
Load Regulation Charts
Efficiency Graph
Ripple Graphs
The lower the power supply's ripple, the more stable the system will be and less stress will also be applied to its components.
Infrared Images
We apply a half-load for 10 minutes with the PSU's top cover and cooling fan removed before taking photos with a modified FLIR E4 camera able to deliver an IR resolution of 320x240 (76,800 pixels).
The hottest area is where the main transformers are installed. Still, temperatures remain low, given the operating conditions.
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